The present invention relates to software patterns and more particularly to modifying a presentation on a client without causing a rewrite of the business logic on the client.
An important use of computers is the transfer of information over a network. Currently, the largest computer network in existence is the Internet. The Internet is a worldwide interconnection of computer networks that communicate using a common protocol. Millions of computers, from low end personal computers to high-end super computers are coupled to the Internet.
The Internet grew out of work funded in the 1960s by the U.S. Defense Department""s Advanced Research Projects Agency. For a long time, Internet was used by researchers in universities and national laboratories to share information. As the existence of the Internet became more widely known, many users outside of the academic/research community (e.g., employees of large corporations) started to use Internet to carry electronic mail.
In 1989, a new type of information system known as the World-Wide-Web (xe2x80x9cthe Webxe2x80x9d) was introduced to the Internet. Early development of the Web took place at CERN, the European Particle Physics Laboratory. The Web is a wide-area hypermedia information retrieval system aimed to give wide access to a large universe of documents. At that time, the Web was known to and used by the academic/research community only. There was no easily available tool which allows a technically untrained person to access the Web.
In 1993, researchers at the National Center for Supercomputing Applications (NCSA) released a Web browser called xe2x80x9cMosaicxe2x80x9d that implemented a graphical user interface (GUI). Mosaic""s graphical user interface was simple to learn yet powerful. The Mosaic browser allows a user to retrieve documents from the World-Wide-Web using simple point-and-click commands. Because the user does not have to be technically trained and the browser is pleasant to use, it has the potential of opening up the Internet to the masses.
The architecture of the Web follows a conventional client-server model. The terms xe2x80x9cclientxe2x80x9d and xe2x80x9cserverxe2x80x9d are used to refer to a computer""s general role as a requester of data (the client) or provider of data (the server). Under the Web environment, Web browsers reside in clients and Web documents reside in servers. Web clients and Web servers communicate using a protocol called xe2x80x9cHyperText Transfer Protocolxe2x80x9d (HTTP). A browser opens a connection to a server and initiates a request for a document. The server delivers the requested document, typically in the form of a text document coded in a standard Hypertext Markup Language (HTML) format, and when the connection is closed in the above interaction, the server serves a passive role, i.e., it accepts commands from the client and cannot request the client to perform any action.
The communication model under the conventional Web environment provides a very limited level of interaction between clients and servers. In many systems, increasing the level of interaction between components in the systems often makes the systems more robust, but increasing the interaction increases the complexity of the interaction and typically slows the rate of the interaction. Thus, the conventional Web environment provides less complex, faster interactions because of the Web""s level of interaction between clients and servers.
A system, method, and article of manufacture provide for an activity module. A server and a presentation interface of a client are interfaced to permit the receipt of requests for service from the presentation interface of the client. A portion of the requests are handled on the client. Another portion of the requests are forwarded to the server for further handling purposes and changes are effected in the presentation interface.
In an aspect of the present invention, a plurality of presentation interfaces may be interfaced. In one embodiment of the present invention, a model may be interfaced for management purposes. In such an embodiment, the model may further include a proxy.
In another embodiment of the present invention, errors and exceptions may also be handled. In a further embodiment of the present invention, events intended to be received may be triggered by the presentation interface.